The deposition of immunglobulins and complement components in the dermal-epidermal junction of patients with systemic lupus erythematosus will be studied along with the deposition of these proteins in the glomeruli of those patients with renal disease. The metabolism of C3, factor B and properdin in the patients will be studied at the time the skin and kidney biopsies are obtained in order to learn more about the pathogenesis of the protein deposition and tissue damage. Patients with chronic discoid lupus and their relatives will be studied to learn whether the observed high levels of properdin are genetically influenced. The immunoglobulin class, and subclass of IgG will be studied in the skin and kidneys and will be correlated with the class and IgG subclass of antibodies to native DNA present in the circulation. The role of the protector proteins, C3b, INA and B1H will be studied in patients with discoid and systemic lupus by determining their serum levels and whether they are deposited in the areas of inflammation or non-involved skin along with other complement proteins.